Product Reviews and Information for Hypothyroidism
Filters
View All
Search term may appear only in full report available to members. Join now for full access.
CL Answer
All About Thyroid Supplements & Desiccated Thyroid Extract (Armour Thyroid)
Learn about supplement ingredients such as iodine, selenium, zinc, acetyl-l-carnitine, ashwagandha and guggul used for thyroid conditions and find out if they are beneficial. Also learn why ingredients such as alpha-lipoic acid, soy, resveratrol, quercetin may impair thyroid function.
CL Answer
I take levothyroxine (Synthroid), a thyroid hormone to treat hypothyroidism. Are there supplements or foods I should avoid, or be taking, due to this drug?
Is taking certain supplements and hypothyroidism medications bad? Learn which supplements can interact with thyroid hormone medications like levothyroxine (Synthroid), thyroid hormone levels, and laboratory tests.
Product Review
Kelp Supplements Review
Choose the Best Kelp Supplement. Be Cautious With Kelp! Only 50% of Supplements Pass CL's Review.
Product Review
Potassium Iodide (KI) and Iodate (KIO3) Radioprotective Pills Review
Learn How to Choose the Best Radioprotective Iodine Pill and Use It Properly
Product Review
Seaweed Snacks and Foods Review
Tests Reveal Seaweed Snack Risks
Product Review
Zinc Supplements, Lozenges, and Melts Review
Find the Best Zinc Supplements, Including Lozenges for Colds.
CL Answer
Does WEEM Grow Hair and Is It Worth It?
WEEM Hair.Skin.Nails is marketed as a "clinically tested hair health blend.” Find out if it — or its ingredients — works for hair loss and if it's worth the price.
Product Review
Multivitamin and Multimineral Supplements Review
32% Failed our Tests. Choose Your Multivitamin Carefully.
CL Answer
Can biotin supplements really strengthen nails or improve hair? Can other supplements help?
Learn more about strengthening brittle nails with vitamin B-7 (biotin), based on clinical evidence.
CL Answer
What are trace minerals and do I need them?
Trace minerals include boron, chromium, copper, iodine, iron, manganese, molybdenum, nickel, zinc, and others. Find out what they do, how much of each trace mineral you should be getting, and who's most likely to be deficient in these minerals.
Product Review
Plant-Based Milks Review (Almond, Cashew, Coconut, Flax, Hemp, Macadamia, Oat, Pea, and Soy)
Find the Best Non-Dairy Milk Alternative. ConsumerLab Tests Reveal What's Really In Plant-Based Milks.
Product Review
NAC (N-Acetyl Cysteine) Supplements Review
Choose the Best NAC Supplement and Save Money
Product Review
Beetroot Juices, Powders, and Chews Review
Our Tests Show Which Beetroot Products Have the Most Nitrate, Least Lead, and Lowest Cost
Product Review
CoQ10 and Ubiquinol Supplements Review
Find the Best CoQ10 and Ubiquinol Supplements and Learn How They Differ
Clinical Update
1/13/2025
Iron & Thyroid Function
Iron deficiency can cause an underactive thyroid (hypothyroidism), but it’s important that iron not be taken at the same time as thyroid medication. Get the details in our Iron Supplements Review, which includes our Top Picks for iron.
Also see our article about supplements and thyroid function.
Clinical Update
1/30/2025
Armour Thyroid: FDA Status
Is Armour Thyroid, a thyroid extract preferred by some people over levothyroxine (Synthroid), approved by the FDA and covered by insurance? Find out in our article about supplements for hypothyroidism.
Clinical Update
6/21/2022
Thyroid Product Caution
Use of a popular thyroid product may interfere with important thyroid tests, according to recent reports. Get the details in our article about Supplements and Hypothyroidism.
Clinical Update
11/05/2021
Fluoride and Hypothyroidism?
Can fluoride in toothpaste affect thyroid function? Find out what research suggests in our updated article about what to look for, or avoid, in toothpaste.
Clinical Update
11/08/2022
Thyroid Concern with NAC
A form of NAC was recently found to contain excess levels of iodide that caused hypothyroidism. Get the details, including the product used and symptoms that occurred, in the Concerns and Cautions section of our NAC Supplements Review.
Clinical Update
11/21/2023
Vitamin D for Thyroid Disease?
Does taking vitamin D improve thyroid function in women with Hashimoto’s thyroiditis? See what a recent study found in the What It Does section of our Vitamin D Supplements Review, which includes our Top Picks for vitamin D.
Also see: I take levothyroxine (Synthroid), a thyroid hormone to treat hypothyroidism. Are there supplements or foods I should avoid, or be taking?
Clinical Update
10/24/2020
How Good Is Generic Thyroid Medication?
How well do people with hypothyroidism do on generic versions of levothyroxine (Synthroid)? We've added new information about this to our article about levothyroxine and dietary supplements.
Clinical Update
9/02/2017
Ashwagandha & Thyroid Function
Ashwagandha extract improved thyroid hormone levels in men and women with subclinical hypothyroidism in a new study. See the details in the "What It Does" section of our Ashwagandha Supplements Review -- which includes our Top Pick among ashwagandha supplements.
Clinical Update
1/28/2018
A Case of Too Much Iodine
A woman with hypothyroidism was hospitalized due to a change in mental state and physical symptoms resulting from getting too much iodine from iodine-containing supplements. For details and upper limits for iodine intake, see the Concerns and Cautions section of the Kelp Supplements Review.
CL Answer
Here’s What You Should Look For In Toothpaste and Mouthwash, and Our Top Picks
Learn about ingredients you want in your toothpaste, mouthwash and other dental products and which ingredients you may want to avoid.
CL Answer
Dietary Supplements and Herbs to Avoid When Breastfeeding
Find out which supplements should be avoided when breastfeeding, including medicinal herbs, soy, and flaxseed.
CL Answer
Are Moringa Leaf Supplements Helpful and Safe?
Are moringa leaf supplements beneficial for diabetes, lowering cholesterol, lowering blood pressure, improving liver function, and other conditions, and are they safe? Find out.
Clinical Update
8/05/2012
Be Careful with Iodine -- Especially If You're Pregnant
Unlike over-the-counter medicines, dietary supplements are generally not required to carry warning labels, even if they contain toxic amounts of ingredients. If you don't know how much of a vitamin, mineral, or other ingredient you really need, it's easily possible to get too much. This is what seems to have happened to some pregnant women taking a widely-sold iodine supplement, according to a recent medical report. Just one tablet contained 57 times the daily iodine they needed and more than ten times the limit associated with increased risk of toxicity. Their children were born with congenital hypothyroidism, apparently due to getting too much iodine from their mothers.
Find out which product these women took in the updated Iodine section of the Multivitamin Supplements Review. You'll also find appropriate levels of other vitamins and minerals and see which products in the Review did or did not exceed tolerable intake levels of vitamins and minerals. More >>
CL Answer
Do hair loss supplements, such as Viviscal, Hair La Vie, and Nutrafol, or topical essential oils work?
Vitamins and supplements that may help with hair loss and thinning, including saw palmetto, beta-sitosterol, protein, iron, and vitamin D.
Product Review
Vitamin D Supplements Review (Including Calcium, Magnesium, Vitamin K, and Boron)
Find the Best Vitamin D Supplement and Avoid Problems
CL Answer
What are the health benefits of palmitoylethanolamide (PEA), and is it safe?
Palmitoylethanolamide (PEA) is commonly promoted for its anti-inflammatory and pain-relieving effects. Find out if it works.
CL Answer
Which vitamins and supplements should be stopped before getting blood work, laboratory tests, or medical imaging?
Find out which vitamins and supplements can interfere with blood, urine or stool tests, and imaginging tests, like bone scans and MRIs. Learn how B vitamins such as biotin, niacin and riboflavin, as well as calcium supplements, St. John’s wort, vitamin C, and others supplements can affect test results, as well as common foods that may interfere with tests.
Recalls & Warnings
September 21, 2023
Moor Herbs, Inc Warned for Manufacturing Violations, Drug Claims
On August 1, 2023, the FDA issued a Warning Letter to Moor Herbs, Inc.
CL Answer
Can taking CoQ10 affect my thyroid levels or interact with my thyroid medication?
Learn more about CoQ10 and thyroid medications along with natural thyroid function. ConsumerLab.com's answer explains.
CL Answer
Which supplements help to improve energy and decrease fatigue?
Energy supplements and vitamins - Some can help increase energy and reduce fatigue, including CoQ10, curcumin/turmeric, cocoa, and B vitamins.
CL Answer
Best Supplements to Prevent Age-Related Muscle Loss
Discover the top supplements to prevent age-related muscle loss after 60. Learn how protein, fish oil, vitamin D, and more can help maintain muscle strength and combat sarcopenia.
CL Answer
Do sea moss and carrageenan have health benefits? Are there risks?
Sea moss is promoted for thyroid health, boosting immunity, improving gut health, and other uses. Find out if it works and learn about possible side effects of sea moss and its constituent, carrageenan.
CL Answer
What is Perque Bone Guard Forté? It is safe and effective for bone health?
Find out about the ingredients in Perque Bone Guard Forté, including which ingredients may be beneficial for osteoporosis and bone health and which may be a safety concern.
CL Answer
Can any supplements reverse gray hair?
Nearly 75% of adults aged 45 to 65 are affected by gray hair. Learn about what causes gray hair and find out if any supplements can help.
Recalls & Warnings
June 13, 2024
Thyroid Supplement Recalled Due to Salmonella
On June 11, 2024, Penn Herb Company Ltd issued a recall of 51 bottles of Nature’s Wonderland Thyroid Formula capsules after FDA testing revealed the products to be contaminated with Salmonella.
Recalls & Warnings
April 23, 2013
Seller of Digestion, Thyroid and Vitamin D Supplements Warned For Drug Claims
On November 5, 2012, the FDA issued a warning letter to The Women's Health Institute at Texas following a review of the company's various websites which found statements made about Digest + SEB, Iodine Plus 2, and D5000 Vitamin D dietary supplements to be drug claims.
Recalls & Warnings
April 08, 2017
Woman Dies After Receiving Turmeric Infusion
On March 16, 2017, a San Diego, California woman died days after receiving an IV infusion of turmeric. Jade Erick, age 30, suffered a brain injury and cardiac arrest after receiving the first 5 mL of a 250 mL infusion of turmeric in the office of a naturopathic doctor.
Recalls & Warnings
January 23, 2014
Many Thyroid Supplements Contain Thyroid Hormones -- Risk of Thyrotoxicosis
A recent study found that 9 out of 10 supplements marketed for "thyroid support" and purchased at retail stores or on the Internet contained actual thyroid hormones thyroxine (T4) and/or triiodothyronine (T3), posing a risk to consumers.
